- Induction therapy study: Patients are entered on stratum 3 (three drugs) for NCI consensus standard-risk disease (age < 10 years and WBC < 50,000/mm³) or stratum 4 (four drugs) induction therapy for NCI consensus high-risk disease (age ≥ 10 years and/or WBC ≥ 50,000/mm³ or CNS3 disease or testicular disease).